No matter what difficulty or map, in every map there are at least 2 out of 7 bots just standing around doing nothing. Everyone of those bots are all the time in the base, just not moving at all.
I first thought, that it has something to do in particular with the engineer class, as bots maybe try to repair buildings but after they repaired them they are kinda stuck. But that is not the case, saw many classes standing pointless around at their base. Most of them will at least attack you, if you attack them.
They would do the same thing when they are in vehicles, also around the base area. In thise case they will just take up one vehicle slot while staying with the vehicle all the time in base and doing nothing.
There is no way to fix this ingame, except for bots in vehicles, as you can enter the vehicle and kick the bot out. In this case the bot will leave the base.